diff --git a/.appveyor.yml b/.appveyor.yml
new file mode 100644
index 000000000..a0d3292f1
--- /dev/null
+++ b/.appveyor.yml
@@ -0,0 +1,23 @@
+build: off
+
+init:
+  - git config --global core.autocrlf input
+
+install:
+  - cinst jdk8 -params 'installdir=C:\\jdk8'
+  - SET JAVA_HOME=C:\jdk8
+  - SET PATH=C:\jdk8\bin;%PATH%
+
+  - ps: |
+      Add-Type -AssemblyName System.IO.Compression.FileSystem
+      if (!(Test-Path -Path "C:\sbt" )) {
+        (new-object System.Net.WebClient).DownloadFile(
+          'https://github.com/sbt/sbt/releases/download/v1.0.4/sbt-1.0.4.zip',
+          'C:\sbt-bin.zip'
+        )
+        [System.IO.Compression.ZipFile]::ExtractToDirectory("C:\sbt-bin.zip", "C:\sbt")
+      }
+  - SET PATH=C:\sbt\sbt\bin;%PATH%
+  - SET SBT_OPTS=-XX:MaxPermSize=2g -Xmx4g -Dfile.encoding=UTF8
+test_script:
+  - sbt "scripted actions/* server/*"
diff --git a/build.sbt b/build.sbt
index ec5065942..dcedffd62 100644
--- a/build.sbt
+++ b/build.sbt
@@ -34,6 +34,7 @@ def buildLevelSettings: Seq[Setting[_]] =
       scmInfo := Some(ScmInfo(url("https://github.com/sbt/sbt"), "git@github.com:sbt/sbt.git")),
       resolvers += Resolver.mavenLocal,
       scalafmtOnCompile := true,
+      scalafmtOnCompile in Sbt := false,
       scalafmtVersion := "1.3.0",
     ))
 
@@ -310,8 +311,7 @@ lazy val commandProj = (project in file("main-command"))
   .settings(
     testedBaseSettings,
     name := "Command",
-    libraryDependencies ++= Seq(launcherInterface, sjsonNewScalaJson.value, templateResolverApi,
-      jna, jnaPlatform),
+    libraryDependencies ++= Seq(launcherInterface, sjsonNewScalaJson.value, templateResolverApi),
     managedSourceDirectories in Compile +=
       baseDirectory.value / "src" / "main" / "contraband-scala",
     sourceManaged in (Compile, generateContrabands) := baseDirectory.value / "src" / "main" / "contraband-scala",
@@ -463,10 +463,9 @@ lazy val sbtIgnoredProblems = {
 }
 
 def runNpm(command: String, base: File, log: sbt.internal.util.ManagedLogger) = {
-  val npm = if (sbt.internal.util.Util.isWindows) "npm.cmd" else "npm"
   import scala.sys.process._
   try {
-    val exitCode = Process(s"$npm $command", Option(base)) ! log
+    val exitCode = Process(s"npm $command", Option(base)) ! log
     if (exitCode != 0) throw new Exception("Process returned exit code: " + exitCode)
   } catch {
     case e: java.io.IOException => log.warn("failed to run npm " + e.getMessage)
diff --git a/main-actions/src/main/scala/sbt/compiler/Eval.scala b/main-actions/src/main/scala/sbt/compiler/Eval.scala
index a075f61a8..a9d97246a 100644
--- a/main-actions/src/main/scala/sbt/compiler/Eval.scala
+++ b/main-actions/src/main/scala/sbt/compiler/Eval.scala
@@ -485,12 +485,10 @@ private[sbt] object Eval {
   def filesModifiedBytes(fs: Array[File]): Array[Byte] =
     if (fs eq null) filesModifiedBytes(Array[File]()) else seqBytes(fs)(fileModifiedBytes)
   def fileModifiedBytes(f: File): Array[Byte] =
-    (if (f.isDirectory) filesModifiedBytes(f listFiles classDirFilter)
+    (if (f.isDirectory)
+       filesModifiedBytes(f listFiles classDirFilter)
      else
-       bytes(
-         try IO.getModifiedTime(f)
-         catch { case _: java.io.FileNotFoundException => 0L })) ++
-      bytes(f.getAbsolutePath)
+       bytes(IO.getModifiedTimeOrZero(f))) ++ bytes(f.getAbsolutePath)
   def fileExistsBytes(f: File): Array[Byte] =
     bytes(f.exists) ++
       bytes(f.getAbsolutePath)
diff --git a/main-command/src/main/java/sbt/internal/NGWin32NamedPipeLibrary.java b/main-command/src/main/java/sbt/internal/NGWin32NamedPipeLibrary.java
index ba535691f..dd4d8f15a 100644
--- a/main-command/src/main/java/sbt/internal/NGWin32NamedPipeLibrary.java
+++ b/main-command/src/main/java/sbt/internal/NGWin32NamedPipeLibrary.java
@@ -29,7 +29,7 @@ import com.sun.jna.ptr.IntByReference;
 
 import com.sun.jna.win32.W32APIOptions;
 
-public interface NGWin32NamedPipeLibrary extends WinNT {
+public interface NGWin32NamedPipeLibrary extends Library, WinNT {
     int PIPE_ACCESS_DUPLEX = 3;
     int PIPE_UNLIMITED_INSTANCES = 255;
     int FILE_FLAG_FIRST_PIPE_INSTANCE = 524288;
diff --git a/main-command/src/main/scala/sbt/internal/server/Server.scala b/main-command/src/main/scala/sbt/internal/server/Server.scala
index 4fb8a7cb4..521c8d399 100644
--- a/main-command/src/main/scala/sbt/internal/server/Server.scala
+++ b/main-command/src/main/scala/sbt/internal/server/Server.scala
@@ -97,7 +97,7 @@ private[sbt] object Server {
             case Failure(e) => ()
             case Success(socket) =>
               socket.close()
-              throw new IOException("sbt server is already running.")
+              throw new AlreadyRunningException()
           }
         } else ()
       }
@@ -210,3 +210,5 @@ private[sbt] case class ServerConnection(
     }
   }
 }
+
+private[sbt] class AlreadyRunningException extends IOException("sbt server is already running.")
diff --git a/main/src/main/scala/sbt/Defaults.scala b/main/src/main/scala/sbt/Defaults.scala
index b006c115d..4fd8d1585 100755
--- a/main/src/main/scala/sbt/Defaults.scala
+++ b/main/src/main/scala/sbt/Defaults.scala
@@ -2315,7 +2315,7 @@ object Classpaths {
         case Some(period) =>
           val fullUpdateOutput = cacheDirectory / "out"
           val now = System.currentTimeMillis
-          val diff = now - IO.getModifiedTime(fullUpdateOutput)
+          val diff = now - IO.getModifiedTimeOrZero(fullUpdateOutput)
           val elapsedDuration = new FiniteDuration(diff, TimeUnit.MILLISECONDS)
           fullUpdateOutput.exists() && elapsedDuration > period
       }
diff --git a/main/src/main/scala/sbt/Main.scala b/main/src/main/scala/sbt/Main.scala
index 6c605056e..da44d0cb8 100644
--- a/main/src/main/scala/sbt/Main.scala
+++ b/main/src/main/scala/sbt/Main.scala
@@ -128,6 +128,9 @@ object StandardMain {
   def initialState(configuration: xsbti.AppConfiguration,
                    initialDefinitions: Seq[Command],
                    preCommands: Seq[String]): State = {
+    // This is to workaround https://github.com/sbt/io/issues/110
+    sys.props.put("jna.nosys", "true")
+
     import BasicCommandStrings.isEarlyCommand
     val userCommands = configuration.arguments.map(_.trim)
     val (earlyCommands, normalCommands) = (preCommands ++ userCommands).partition(isEarlyCommand)
diff --git a/main/src/main/scala/sbt/internal/CommandExchange.scala b/main/src/main/scala/sbt/internal/CommandExchange.scala
index 39259ee28..d7b52280d 100644
--- a/main/src/main/scala/sbt/internal/CommandExchange.scala
+++ b/main/src/main/scala/sbt/internal/CommandExchange.scala
@@ -10,7 +10,7 @@ package internal
 
 import java.io.IOException
 import java.util.concurrent.ConcurrentLinkedQueue
-import java.util.concurrent.atomic.AtomicInteger
+import java.util.concurrent.atomic._
 import scala.collection.mutable.ListBuffer
 import scala.annotation.tailrec
 import BasicKeys.{
@@ -26,7 +26,7 @@ import sjsonnew.JsonFormat
 import sjsonnew.shaded.scalajson.ast.unsafe._
 import scala.concurrent.Await
 import scala.concurrent.duration.Duration
-import scala.util.{ Success, Failure }
+import scala.util.{ Success, Failure, Try }
 import sbt.io.syntax._
 import sbt.io.{ Hash, IO }
 import sbt.internal.server._
@@ -48,6 +48,7 @@ private[sbt] final class CommandExchange {
   } getOrElse true
   private val lock = new AnyRef {}
   private var server: Option[ServerInstance] = None
+  private val firstInstance: AtomicBoolean = new AtomicBoolean(true)
   private var consoleChannel: Option[ConsoleChannel] = None
   private val commandQueue: ConcurrentLinkedQueue[Exec] = new ConcurrentLinkedQueue()
   private val channelBuffer: ListBuffer[CommandChannel] = new ListBuffer()
@@ -90,7 +91,6 @@ private[sbt] final class CommandExchange {
     else s
   }
 
-  private def newChannelName: String = s"channel-${nextChannelId.incrementAndGet()}"
   private def newNetworkName: String = s"network-${nextChannelId.incrementAndGet()}"
 
   /**
@@ -132,7 +132,8 @@ private[sbt] final class CommandExchange {
       subscribe(channel)
     }
     server match {
-      case Some(_) => // do nothing
+      case Some(_)                    => // do nothing
+      case None if !firstInstance.get => // there's another server
       case _ =>
         val portfile = (new File(".")).getAbsoluteFile / "project" / "target" / "active.json"
         val h = Hash.halfHashString(IO.toURI(portfile).toString)
@@ -149,15 +150,27 @@ private[sbt] final class CommandExchange {
                            socketfile,
                            pipeName)
         val x = Server.start(connection, onIncomingSocket, s.log)
-        Await.ready(x.ready, Duration("10s"))
+
+        // don't throw exception when it times out
+        val d = "10s"
+        Try(Await.ready(x.ready, Duration(d)))
         x.ready.value match {
           case Some(Success(_)) =>
             // rememeber to shutdown only when the server comes up
             server = Some(x)
+          case Some(Failure(e: AlreadyRunningException)) =>
+            s.log.warn(
+              "sbt server could not start because there's another instance of sbt running on this build.")
+            s.log.warn("Running multiple instances is unsupported")
+            server = None
+            firstInstance.set(false)
           case Some(Failure(e)) =>
             s.log.error(e.toString)
             server = None
-          case None => // this won't happen because we awaited
+          case None =>
+            s.log.warn(s"sbt server could not start in $d")
+            server = None
+            firstInstance.set(false)
         }
     }
     s
@@ -191,6 +204,7 @@ private[sbt] final class CommandExchange {
       case xs =>
         lock.synchronized {
           channelBuffer --= xs
+          ()
         }
     }
   }
@@ -247,6 +261,7 @@ private[sbt] final class CommandExchange {
       case xs =>
         lock.synchronized {
           channelBuffer --= xs
+          ()
         }
     }
   }
@@ -288,6 +303,7 @@ private[sbt] final class CommandExchange {
       case xs =>
         lock.synchronized {
           channelBuffer --= xs
+          ()
         }
     }
   }
@@ -339,6 +355,7 @@ private[sbt] final class CommandExchange {
       case xs =>
         lock.synchronized {
           channelBuffer --= xs
+          ()
         }
     }
   }
diff --git a/main/src/main/scala/sbt/internal/LibraryManagement.scala b/main/src/main/scala/sbt/internal/LibraryManagement.scala
index fc832ffff..d247a9d99 100644
--- a/main/src/main/scala/sbt/internal/LibraryManagement.scala
+++ b/main/src/main/scala/sbt/internal/LibraryManagement.scala
@@ -127,7 +127,7 @@ private[sbt] object LibraryManagement {
   }
 
   private[this] def fileUptodate(file: File, stamps: Map[File, Long]): Boolean =
-    stamps.get(file).forall(_ == IO.getModifiedTime(file))
+    stamps.get(file).forall(_ == IO.getModifiedTimeOrZero(file))
 
   private[sbt] def transitiveScratch(
       lm: DependencyResolution,
diff --git a/project/Dependencies.scala b/project/Dependencies.scala
index f8e14429f..21de56080 100644
--- a/project/Dependencies.scala
+++ b/project/Dependencies.scala
@@ -12,10 +12,10 @@ object Dependencies {
   val baseScalaVersion = scala212
 
   // sbt modules
-  private val ioVersion = "1.1.2"
-  private val utilVersion = "1.1.1"
-  private val lmVersion = "1.1.1"
-  private val zincVersion = "1.1.0-RC3"
+  private val ioVersion = "1.1.3"
+  private val utilVersion = "1.1.2"
+  private val lmVersion = "1.1.2"
+  private val zincVersion = "1.1.0-RC4"
 
   private val sbtIO = "org.scala-sbt" %% "io" % ioVersion
 
@@ -106,8 +106,6 @@ object Dependencies {
   val specs2 = "org.specs2" %% "specs2-junit" % "4.0.1"
   val junit = "junit" % "junit" % "4.11"
   val templateResolverApi = "org.scala-sbt" % "template-resolver" % "0.1"
-  val jna = "net.java.dev.jna" % "jna" % "4.1.0"
-  val jnaPlatform = "net.java.dev.jna" % "jna-platform" % "4.1.0"
 
   private def scala211Module(name: String, moduleVersion: String) = Def setting (
     scalaBinaryVersion.value match {
diff --git a/project/Scripted.scala b/project/Scripted.scala
index 932d55a0f..788f1d60e 100644
--- a/project/Scripted.scala
+++ b/project/Scripted.scala
@@ -37,6 +37,9 @@ trait ScriptedKeys {
 }
 
 object Scripted {
+  // This is to workaround https://github.com/sbt/io/issues/110
+  sys.props.put("jna.nosys", "true")
+
   lazy val MavenResolverPluginTest = config("mavenResolverPluginTest") extend Compile
   lazy val RepoOverrideTest = config("repoOverrideTest") extend Compile
 
diff --git a/project/SiteMap.scala b/project/SiteMap.scala
index 2cfb5d8ea..95e038eab 100644
--- a/project/SiteMap.scala
+++ b/project/SiteMap.scala
@@ -68,8 +68,8 @@ object SiteMap {
   // generates a string suitable for a sitemap file representing the last modified time of the given File
   private[this] def lastModifiedString(f: File): String = {
     val formatter = new java.text.SimpleDateFormat("yyyy-MM-dd")
-    // TODO: replace lastModified() with sbt.io.Milli.getModifiedTime(), once the build
-    // has been upgraded to a version of sbt that includes sbt.io.Milli.
+    // TODO: replace lastModified() with sbt.io.IO.getModifiedTimeOrZero(), once the build
+    // has been upgraded to a version of sbt that includes that call.
     formatter.format(new java.util.Date(f.lastModified))
   }
   // writes the provided XML node to `output` and then gzips it to `gzipped` if `gzip` is true
diff --git a/project/Util.scala b/project/Util.scala
index 0b87b02db..8c68f4ced 100644
--- a/project/Util.scala
+++ b/project/Util.scala
@@ -105,8 +105,8 @@ object Util {
     val timestamp = formatter.format(new Date)
     val content = versionLine(version) + "\ntimestamp=" + timestamp
     val f = dir / "xsbt.version.properties"
-    // TODO: replace lastModified() with sbt.io.Milli.getModifiedTime(), once the build
-    // has been upgraded to a version of sbt that includes sbt.io.Milli.
+    // TODO: replace lastModified() with sbt.io.IO.getModifiedTimeOrZero(), once the build
+    // has been upgraded to a version of sbt that includes that call.
     if (!f.exists || f.lastModified < lastCompilationTime(analysis) || !containsVersion(f, version)) {
       s.log.info("Writing version information to " + f + " :\n" + content)
       IO.write(f, content)
diff --git a/project/build.properties b/project/build.properties
index 94005e587..394cb75cf 100644
--- a/project/build.properties
+++ b/project/build.properties
@@ -1 +1 @@
-sbt.version=1.0.0
+sbt.version=1.0.4
diff --git a/project/plugins.sbt b/project/plugins.sbt
index 66097a8b9..7ea70f8ea 100644
--- a/project/plugins.sbt
+++ b/project/plugins.sbt
@@ -1,8 +1,7 @@
-scalaVersion := "2.12.3"
+scalaVersion := "2.12.4"
 scalacOptions ++= Seq("-feature", "-language:postfixOps")
 
-addSbtPlugin("org.scala-sbt" % "sbt-houserules" % "0.3.4")
+addSbtPlugin("org.scala-sbt" % "sbt-houserules" % "0.3.5")
 addSbtPlugin("org.scala-sbt" % "sbt-contraband" % "0.3.2")
-addSbtPlugin("com.lucidchart" % "sbt-scalafmt" % "1.14")
 addSbtPlugin("de.heikoseeberger" % "sbt-header" % "3.0.2")
 addSbtPlugin("com.eed3si9n" % "sbt-buildinfo" % "0.7.0")